Pass

_I recognise the struggle, därför får du inte komplettering._

## Komplettering (egentligen inte) (som den hade sett ut)

**Superbra jobbat!!!**

I love your bit maps!

To pass this assignment you must test and implement `GameState::Check` and promotion.

My only critique is that your `Game` structure is big in memory due to all masks. Since the masks do not change in value, you're able to instead declare them as global contants, thus saving memory usage.

Locate GameState::Check, the promotion logic, and the existing test setup in the repository. First review how these chess rules are currently represented, then add coverage and implementation for Check and promotion. Done means the relevant tests pass and the unchanged masks are moved to global constants as requested.

Written by the indexing model from the issue text.